JPH01250073A - Multichannel thermistor type anemoscope - Google Patents

Abstract

PURPOSE:To accurately take a measurement without disordering a flow of wind by arranging a thermistor for wind temperature detection at the peak part of a pyramidal holding member and thermistors for wind velocity detection at side parts, and measuring the velocity, direction, and temperature of the wind with detection signals from plural positions of said holding member. CONSTITUTION:The wind temperature detecting thermistor 1 is arranged at the peak part of the nearly pyramidal holding member 5 and the wind velocity detecting thermistors 2a-2b are arranged at four base sides of said member 5 to constitute a pyramid sensor 10. Many sensors 10 like this are provided and each sensor is set for one channel; and a wind velocity signal and a wind direction signal are outputted with the signals of the sensors 10 and those signals are inputted to an anemoscope control circuit together with signals outputted by other sensors 10 to detect the direction, velocity, and temperature of the wind.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a wind vane constructed using a thermistor.
The present invention relates to a direct heating constant current type thermistor type wind vane, and in particular to a multi-channel thermistor type wind vane that can detect wind direction, wind speed, etc. based on data measured using a plurality of pyramid sensors.

(Prior art) Generally, in order to measure the flow velocity of a fluid such as air, that is, wind speed, etc., a mechanical rotating axis such as a vertical axis, as typified by a weather vane, is used to measure the wind pressure. In many cases, devices that indicate wind direction by being rotated are used. Further, a means is used in which a windmill is installed in the weather vane so that the number of rotations of the windmill is proportional to the wind speed, so that the wind speed can also be displayed at the same time.

Apart from the devices mentioned above, devices such as pitot tubes are sometimes used for air flows flowing at relatively high speeds, and in the case of this device, the value of the square of the wind speed is ,
It uses the principle that it is proportional to pressure.

Wind speeds commonly used as described above,
Devices such as wind vanes are devices that can relatively easily measure wind speed and the like, and can provide relatively accurate measured values.

However, the value obtained by the general measuring device mentioned above is the average value of the wind speed within a certain period of time, and it does not measure the instantaneous wind speed or the change in wind speed within a very short period of time. It is impossible to do so. In addition, in the case of devices that have mechanical operating members, there are problems with durability and disadvantages such as the inability to measure minute flows due to effects such as shaft friction. be.

On the other hand, hot wire anemometers and the like are often used as a method of measuring changes in wind speed, etc. within a very short period of time. This hot wire anemometer uses a thermistor, and takes advantage of the fact that the resistance value of the thermistor changes depending on the temperature. In order to measure the wind speed as described above, a measured value can be easily obtained by measuring the change in the current flowing through a thermistor incorporated in the bridge circuit.

Furthermore, anemometers using thermistors as described above are not only applicable to gaseous fluids such as air, but can also be used as a means of measuring the flow velocity of fluids such as water and oil. is possible and can be applied to many types of fluids.

(Problem to be Solved by the Invention) Regarding the wind speed resistance J5 using a thermistor as described above, there is a characteristic that the resistance value of the thermometer used therein changes depending on the temperature, and the resistance value depending on the temperature A device is provided to eliminate the effects of value changes.

This device is equipped with a temperature measurement means separate from the part that measures changes in humidity due to fluid flow.The temperature change obtained by the temperature measurement means is input to the control device, and the flow rate is adjusted according to the value. An f-stage is used that corrects the input value from the measurement section.

Furthermore, a thermistor is generally used as the above-mentioned temperature measuring means.

However, when a bridge circuit is provided in the conventional thermistor current meter as described above, it is necessary to use an element with a relatively large heat capacity g as a temperature correction element.

In addition, since it is necessary to use a relatively highly sensitive thermistor for detecting flow velocity, it is not possible to use thermistors of the same standard for all such thermistors, and it is necessary to use them according to the characteristics of each. The problem is that a thermistor must be used.

Therefore, for the reasons mentioned above, thermistors with different performances are used in the two measuring parts, and
It is necessary to incorporate control circuits corresponding to each, and for these reasons, there is a drawback that the shape of the sensor device becomes large.

In addition, instead of the above-mentioned device using a conventional thermistor, as shown in FIG. . . . as well as the substrate 4
A flow sensor 40 configured by arranging an air temperature detection member 42 in the center of the flow sensor 1 may be used.

And for sensors like the ones mentioned above.

By generating heat in the platinum film, the resistance values of opposing elements are compared using a bridge circuit to detect the wind direction.

However, in the conventional device as described above,
Because it uses a platinum thin film and its measurement sensitivity is low,
The disadvantage is that the circuit configuration of the control device is complicated and it is susceptible to electromagnetic noise.

Further, since the wind speed sensing element is provided on the same plane facing the wind temperature sensing member 42, and these elements are easily influenced by heat, there is a problem of large measurement errors. be. In addition, in order to manufacture the above-mentioned sensor, problems such as the need for large-scale manufacturing equipment arise.

(Objective of the Invention) The present invention solves the drawbacks of conventionally used devices as described above, and has a simple configuration.
The purpose of this invention is to obtain a device that can accurately measure wind direction, wind temperature, and wind speed in a narrow space without the wind direction sensor itself disturbing the flow of air, etc.

(Means for Solving the Problems and nm) The multi-channel thermistor type wind vane of the present invention has a substantially pyramid-shaped holding member with a wind temperature detection thermistor on the top and a plurality of wind speed detection on the sides. Thermistors are arranged and provided, and the values detected by each sensor are input to the wind vane detection circuit, and I! IW detection thermistor signal,
It is configured to process signals from a plurality of wind speed detection thermistors and output two signals, a wind speed signal and a wind direction signal, and by arranging a large number of the pyramid sensors, the wind speed obtained by each pyramid sensor is This device is configured so that three types of data, wind direction, wind speed, and wind temperature, can be obtained and displayed on the display unit by sequentially inputting the signal and the wind direction signal to the control device of the wind vane. be.

In addition, the sensor of the present invention uses a directly heated constant current type thermistor type current meter, in which four wind speed detection thermistors are arranged corresponding to each side of a pyramid-shaped holding member, and one A wind temperature detection thermistor is provided at the top, and such a combination member is configured as a single channel wind direction sensor.

A large number of sensors composed of thermistors as described above are arranged, and a wind speed or wind temperature detection circuit is provided for each thermistor of each channel. Then, these output signals are divided into two types of signal lines and output in order as one wind temperature signal and four wind speed signals for each channel, and the wind speed and wind temperature signals at the wind vane are output in order. The signal q input to the processing circuit and processed by the wind vane can be displayed on the display section in the form of a graph or numbers.

Therefore, since the multi-channel thermistor type wind vane of the present invention does not have mechanical rotating members, it is air resistant, and the thermistor has high sensitivity, so it can measure weak flows in good conditions. It is something that can be done.

In addition, the multi-channel thermistor type wind vane of the present invention has a simplified circuit configuration, is less susceptible to external noise such as electromagnetic noise, and the thermistor provided on the pyramid-shaped holding member is the same. It can be constructed from standard materials, and the sensor can be made smaller.

(Example) The configuration of a multi-channel thermistor type wind vane of the present invention will be explained according to the illustrated example.

As shown in FIG. 1, the pyramid sensor 10 of the present invention has an air temperature detection thermistor 1 disposed at the top of a substantially pyramid-shaped holding member 5, and 4
Wind speed detection thermistors 2a, 2b and
...is placed.

Then, the spacer 6 provided at the lower part of the holding member 5 is
It can be attached to a support member 7 protruding from the frame of the measuring device and set in a place where wind speed, etc. is to be measured. A signal line is provided to send signals.

In the multi-channel thermistor type wind vane of the present invention,
A large number of pyramid sensors 10 as described above are provided, and each pyramid sensor is set as one channel, and the measured values from many channels are sequentially input to the wind speed detection circuit, and the detected information from those sensors is used. Information such as wind direction, wind speed, and wind temperature can be output to the display section of the device.

The graph shown in FIG. 2 shows an example of the measurement data of the wind direction shade in the device of the present invention. The pyramid sensor 10 is accurately positioned in each direction N-8, and the wind direction is the E direction. , the values detected by each wind speed detection thermistor of the pyramid sensor are N, S
It shows a state that strongly appears in the direction.

The above-mentioned measurement results are input to a control device having a configuration as shown in FIG. 3, and a predetermined process II fI is performed by the signal processing circuit of the control S@.

In the control circuit of the present invention shown in FIG. 3, signals from a large number of pyramid sensors 10 are transmitted to channels 1.
From 2.3...n, the wind vane 20 is manually operated.

This wind vane 20 receives input from a detection circuit 21 arranged corresponding to each channel to a scanner circuit 22, and from the scanner circuit 22, signals of wind speed and wind temperature are sent to the following amplifier circuits 24 and 27. is output.

In the wind direction if 20 control circuit of the present invention, a linearizer 25.28 is connected to the amplifier circuit 24.27,
Each of those signals is outputted to the A/D conversion circuit 30 via the multiplexer 29, and from the A/D conversion circuit 30, R823
Through the 2C conversion circuit 31, the personal computer 32
The wind direction, wind speed, and wind temperature are output from the personal computer 32 to the display section as output data in the form of a graph signal or numerical signal.

In the above control circuit of the present invention, 0? The detection circuit 21 described in I is configured such that a detection circuit corresponding to each channel processes a signal input from each channel corresponding to the channel of each sensor. The detected signal processed by the scanner circuit 22 is outputted to the scanner circuit 22.

Detection circuit: The detection circuit 21 is composed of a temperature measurement circuit and a flow rate measurement circuit, and includes amplifier circuits 24, 27, and 14.
Together with the m correction circuit 26 and the linearizers 25 and 28, it processes the detected values from the sensor.

In the temperature measurement circuit, the change in resistance value due to temperature of the thermistor for wind temperature measurement is converted into a voltage signal, and it is possible to correct not only the temperature display but also the temperature dependence of the sensor for wind speed measurement. It is being done.

Further, these circuits are provided with a constant current circuit connected to a constant voltage power supply, a normal voltage circuit, a bridge circuit into which the measured value of the III temperature measuring thermistor is inputted, and the like.

The wind speed measurement circuit includes a flow speed zero point correction circuit, an amplifier circuit 27,
It is composed of a wind temperature correction circuit 26, a linearizer 28, etc., and the measured value from the wind speed detection thermistor is calculated as an output voltage corresponding to the temperature based on the relationship between flow speed sensitivity and temperature characteristics in the negative resistance region of the thermistor. is obtained, and by multiplying the output voltage by a correction coefficient, it is possible to output a signal that is not affected by the ambient temperature.

Scanner circuit and control circuit: The scanner circuit 22 is a differential input type C-MO capable of digital control of n×5 (number of channels plus number of mister sensors).
It is composed of a group of S switches and a set of C-Mo5 switches of the same standard that discriminate between wind temperature signals and wind speed signals.

The operation of each of these switches is digitally controlled by the control circuit 23, and the on/off control operation of each switch is performed.

Further, the output from the scanner circuit 22 described above is transmitted to channel 1 in the order of wind temperature data and wind speed data 1.2.3.4 corresponding to each sensor of the pyramid sensor.
Then, channel 2, channel 3
...... will be output one after another.

Multiplexer: The multiplexer 29 combines the wind temperature signal classified by the scanner circuit 22 and the speed signal into the same signal line again. , is a circuit for outputting to the A/D conversion circuit 30.

A/D conversion circuit; In the A/DI conversion circuit 30, the analog signals combined by the two multiplexers are converted into a 10-bit digital signal (parallel) and outputted to the R8232C conversion circuit 31.

R8232C conversion circuit: This R8232C conversion circuit 31 can be a commercially available one, and converts the 10-bit parallel signal output from the Δ/D conversion circuit into a serial signal using the R8232C, and sends it to the micro combiator 32. and output it.

Vernal computer; configured to process input data according to a program set for the multi-channel thermistor type wind direction set of the present invention. That is, the four wind speed detection sensors of the pyramid sensor are NSE, S, W, and the wind speed data from each sensor is n, e, s,
Assuming w, the wind direction can be found by the following procedure.

(1) Arrange in descending order of wind speed value.

(2) Determine the quadrant.

The position of the large wind speed detection thermistor is N-+W→S-+
If they are adjacent in E's cycle, a) In the case of E and N... 1st quadrant B) In the case of N and W...
2nd quadrant) In the case of W and S...3rd quadrant)
In the case of S and E...-4th quadrant, however, large 2
The positions of the two wind speed detection thermistors are N-+W-8-+E
If they are not adjacent to each other, the position with the third largest value is unconditionally set as the wind direction.

(3) As shown in Fig. 4, calculate the wind direction coefficient α such that α=(e+w)/(n+s>).

However, in the case of the first and third quadrants, the above α is 1/α−
If (n+s)/(e+w), in each quadrant,
In the angular range from 0 to 90', coefficients α having the same characteristics can be obtained as shown in the graph shown in FIG.

Therefore, the wind direction angle θ in each quadrant is θ=f(α
)+CI C1: Can be obtained by correction coefficient.

In addition, when calculating the wind speed value, it is possible to obtain an accuracy of about ±20% by taking the maximum value of the output values rearranged using the above formula (1), but since the wind direction angle θ is obtained, , the wind direction can be corrected using the following formula.

ff1l value: V=VHax + (V (θ)+02
) vHaX: Maximum value of four wind speed values C2: Correction coefficient As mentioned above, the multi-channel thermistor type wind direction of the present invention is an application of a DC constant current type thermistor type current meter as an anemometer; Wind speed detection thermistor 2
and one wind temperature detection thermistor 1 are attached to the top and four sides of the pyramid-shaped holding member 5, respectively, to form a pyramid sensor.

Then, a large number of pyramid sensors are each set as one channel, and the detected values of those sensors are inputted to the scanner circuit 22 via the detection circuit 21, and the scanner circuit 22 controlled by the control circuit 23 , C-MO, S switches process the wind speed and wind temperature signals from each thermistor from each pyramid sensor.

- Signals from each channel are sequentially output through two signal lines, and one wind temperature signal is converted by the amplifier circuit 24 and linearizer 25 into a signal corresponding to the actual temperature. In addition, the four wind speed signals are transmitted to an amplifier circuit 27 and a wind temperature correction circuit 26 whose input is a signal corresponding to the actual temperature.
and the linearizer 28 convert it into a signal corresponding to the actual wind speed value.

The two types of signals obtained as described above are inputted again to the multiplexer 29 and integrated into one type of signal line,
This signal is converted into a digital signal by the A/D conversion circuit 30, then converted into a serial signal by the R3232C conversion circuit 31, and inputted to the personal computer 32 via the RS 232C cable.

In the personal computer 32, the wind direction is calculated from the magnitude relationship of the four wind speed values, and three types of data, wind direction, wind speed, and wind temperature, are displayed on the display unit in numbers or graphs.

Therefore, the multi-channel thermistor type wind vane of the present invention is made up of only a nermistor and a control circuit, so it is durable and the thermistor has high sensitivity, making it possible to measure even in weak flows. It has the advantage of being simple in circuit configuration and less susceptible to external noise such as electromagnetic noise.

Furthermore, all five thermistors attached to the pyramid sensor are of the same standard and can be very small, so it is possible to reduce the shape of the pyramid-shaped holding member.

Furthermore, in the device of the present invention, the wind temperature detection thermistor is placed at the top of the pyramid, and the four wind speed detection thermistors are placed at each base of the pyramid, and these thermistors are arranged three-dimensionally. , and have a structure that makes them less susceptible to heat influences.

Therefore, the multi-channel thermistor type wind vane of the present invention has high accuracy in measuring wind temperature and wind speed, and
Since the method directly measures the wind speed value and determines the wind direction from the magnitude relationship, there is no need to provide a separate thermistor for wind speed measurement.

Moreover, the pyramid of the present invention can easily be given planar directivity and can be applied as a three-dimensional sensor. Furthermore, since the device of the present invention uses a C-MOS switch in the scanner circuit, there is no mechanical contact, so the device has a long life and can speed up processing operations.

In the multi-channel thermistor type wind vane of the present invention as described above, as a pyramid sensor, FIGS.
It is possible to use an apparatus having the configuration shown in (e).

In the embodiment shown in FIG. 6, in order to prevent the wind speed detecting thermistor from disturbing or otherwise causing the wind to flow, the mounting portion of the wind speed detecting thermistor is formed in a recessed portion. The structure is such that the wind hitting one wind speed detection thermistor does not affect other wind speed detection thermistors.

For example, in the example shown in FIG. 5A, the holding member 10a is formed in a pyramid shape, but as described above, the wind speed detection thermistor 2 is provided in four parts.

In addition, in the example shown in FIG.
0b is configured in the shape of a square block, and a wind temperature detection thermistor 1 is placed in the center of the top surface, and four wind speed detection thermistors 2 are placed in the other four side portions through recesses, respectively.
Place.

In the embodiment shown in FIG.
c is formed into a substantially triangular shape, with a wind temperature detection thermistor 1 disposed in the center of the upper surface, and wind speed detection thermistors 2 provided through recesses in the three side portions of the pond.

Roughly speaking, in the example shown in FIG. 3(d), a wind temperature detection thermistor 1 and a wind speed detection thermistor 2, which is not affected by the wind flow with respect to the XY plane, are installed at predetermined positions on the rod-shaped holding member 10d. Only one of each is provided. Therefore, the part to which the wind direction detection thermistor 3 is attached is provided on a member formed in a special shape, such as the protruding member 10e, so that the influence of wind flow can be identified, so that the wind speed, direction, and temperature can be determined. The system is constructed so that it is possible to measure both at the same time.

In each of the embodiments described above, after constructing the holding member,
This is an example in which a thermistor is attached to a specific part of the holding member, but in the device J3 of the present invention, as shown in FIG. 7, the pyramid-shaped holding member 5 is integrally made of ceramic. , by providing an electrode at a predetermined portion thereof, printing a thick film of thermistor on the electrode, and further sintering, the pyramid sensor 10 is manufactured.
It is also possible to create

In addition, in the multi-channel thermistor type wind vane of the present invention, conditions such as the number of pyramid sensors are determined by the object to be measured, and the conditions such as the wind direction and wind speed inside a relatively small mechanical device are determined by the object to be measured. When measuring , the number of pyramid sensors placed inside the device may be small.

On the other hand, when measuring the overall wind flow etc. in a relatively large device, it is necessary to use many pyramid sensors to precisely measure the wind direction, wind speed, etc. inside the device. This makes it possible to obtain measured values in the current state.

In addition, the sensor of the present invention is configured so that wind flow from the Z-axis direction can be cut, especially when configured as a device as shown in FIG. By changing the individual axes and arranging them in combination, it can be used as a three-dimensional wind direction sensor.

The sensor of the present invention can easily detect the wind direction, wind speed, etc. in a mechanical device by appropriately selecting the combination state. It can also be used as a measuring device for measuring the flow of water, etc., making it possible to construct a handy measuring device.

(Effects of the Invention) Since the multi-channel thermistor type wind vane of the present invention has the above-described configuration, the pyramid sensor can be configured as a very small device, and the entire measuring device can be configured in a small size. It is possible to improve measurement accuracy.

In addition, the multi-channel thermistor type wind vane of the present invention does not disturb the flow of wind due to the pyramid sensor, so it can be used to measure wind direction, wind speed, wind temperature, etc. inside very narrow mechanical devices. This can be particularly effective when measuring the flow of cooling air in equipment such as photocopying.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the pyramid sensor of the present invention, FIG. 2 is a graph showing the status of measured values by the pyramid sensor of the present invention, FIG. 3 is a block diagram showing the configuration of the control circuit of the present invention, and FIG. is a graph showing the angular characteristics of the wind direction coefficient α,
Figure 5 is a graph showing the angular characteristics of the wind direction coefficient α converted into angular displacement from 0 to 90° in the first and third quadrants of the graph in Figure 4, with α-1/α in each quadrant. ,
6(a) to 6(d) are explanatory diagrams showing other shapes of the pyramid sensor of the present invention, respectively. FIG. 7 is a perspective view of an example in which the pyramid sensor is constructed in a ceramic body; The figure is an explanatory diagram showing the configuration of a conventional sensor. Reference numerals in the figure 1... Wind temperature detection thermistor, 2... Wind speed detection thermistor, 5... Holding member, 10...
... Pyramid sensor, 20 ... Wind vane, 21 ... Detection circuit, 22 ... Scanner circuit, 23 ... Control circuit, 24.
...Amplification circuit, 25...Linearizer,
26...Air temperature correction circuit, 27...Amplification circuit, 28...Linearizer, 29...
・Multiplexer, 30...A/D conversion circuit,
31...R8232C conversion circuit, 32...
··Personal computer. Figure 1 Figure 2 Figure 4 Figure 5 Figure 4/

Claims (1)

[Claims] A substantially pyramid-shaped holding member is provided with a wind temperature detection thermistor on the top and a plurality of wind speed detection thermistors on the sides, and the values detected by each sensor are It is configured to be input to the detection circuit of the wind vane, process the signal of the wind temperature detection thermistor and the signal from the plurality of wind speed detection thermistors, and output two signals, a wind speed signal and a wind direction signal, By arranging a large number of pyramid sensors and sequentially inputting the wind speed signal and wind direction signal obtained by each pyramid sensor to the wind vane control device, three types of data: wind direction, wind speed, and wind temperature can be obtained. A multi-channel thermistor type wind vane characterized in that it is configured such that the obtained information can be displayed on a display section.